fix: Prevent duplicate expressions in DynamicPhysicalExpr

[UBarney]

Which issue does this PR close?

• ClosesConsumer receives duplicate bound predicates when join mode is CollectLeft #17541.

Rationale for this change

What changes are included in this PR?

Refine report_partition_bounds Logic in shared_bounds.rs:

• The partition parameter has been renamed to left_side_partition_id to clarify that it refers to the partition from the left (build) side.
• New deduplication logic has been added: it skips reporting bounds if the current left_side_partition_id is identical to the previously recorded one. This directly fixes the issue in CollectLeft mode, where all streams report the same left_side_partition_id of 0, thus preventing duplicate expressions.

Are these changes tested?

Yes

Are there any user-facing changes?

No

[UBarney]

FYI @adriangb

[adriangb]

Thanks!